Arctic Aven — ruling 1

Multiple instances of lifelink aren't cumulative. Activating Arctic Aven's ability more than once during a single turn won't cause you to gain more life.

Arctic Aven : règles, fonctionnement et interactions (MTG)

Arctic Aven is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Flying This creature gets +1/+1 as long as you control a Plains. : This creature gains lifelink until end of turn. (Damage dealt by this creature also causes you to gain that much life.)

How it works : Arctic Aven

Original English text — Wizards of the Coast / Scryfall

#1July 1, 2012· Wizards of the Coast
Multiple instances of lifelink aren't cumulative. Activating Arctic Aven's ability more than once during a single turn won't cause you to gain more life.
No other card is named in this ruling.